Packet

A packet is a class used by the API to represent a message sent or received by the server.
The good practice to create a packet is to use the PacketBuilder class.

The class can be used to send a packet to a client or a server (the class will be exploited by the API) or when you receive a new packet.

Packet Header Props

Here is how the packet header is structured:

tools/packet/props/header.hpp

struct PacketHeaderProps {
    unsigned payloadLength: kPacketHeaderPayloadLengthSize = 0; // 0..1023  (10 bits)
    unsigned payloadType: kPacketHeaderPayloadTypeSize = 0;     // 0..15    (4 bits)
    unsigned offsetFlag: kPacketHeaderFlagSize = 0;             // 0..1     (1 bit)
    unsigned turnFlag: kPacketHeaderFlagSize = 0;               // 0..1     (1 bit)
};

The header is mainly used by the API to determine the packet type and the payload length.
You can use it by calling the GetHeaderProps method from the packet class.

warning

If you manually create a packet, you must set the header properties correctly. All the properties are documented with Bit Fields

The constants values are defined in header.hpp but you can also find documentation about bits allocation in Network Protocol - Header.

Packet Message Props

Here is how message props are structured:

tools/packet/props/message.hpp

struct PacketMessageProps {
    unsigned messageId: kPacketMessageIdSize = 0;     // 0..1048575 (20 bits)
    unsigned messageType: kPacketMessageTypeSize = 0; // 0..63      (6 bits)
    unsigned : 6;
};

The last 6 bits are used for padding and are not used by the API.
The message props are not used by the API and are mainly used by the client/server to determine the message type and the message id.
You can use it by calling the GetMessageProps method from the packet class.

Packet Offset Props

Here is how offset props are structured:

tools/packet/props/offset.hpp

struct PacketOffsetProps {
    unsigned offset: kPacketOffsetSize = 0;         // 0..32767 (15 bits)
    unsigned offsetFlag: kPacketOffsetFlagSize = 0; // 0..1 (1 bit)
};

This structure is optional and is used to determine the offset of the packet.
This part is used by the API for Multi Packets.

info

If you try to get offset props from a packet that does not have an offset (offset flag to 0 in the header), the API will throw an exception.
You can use packetInstance.OffsetIsEnabled() to check if the packet has an offset.

Packet Turn Props

Here is how turn props are structured:

tools/packet/props/turn.hpp

struct PacketTurnProps {
    unsigned turn: kPacketTurnSize = 0; // 0..65535 (16 bits)
};

This structure is optional and is used to determine the turn of the packet.
It's not used by the API and is mainly used by the client/server to determine the turn of the packet in case of multi stats payload for example.

info

If you try to get turn props from a packet that does not have a turn (turn flag to 0 in the header), the API will throw an exception.
You can use packetInstance.TurnIsEnabled() to check if the packet has an turn.

Packet Payload

The packet payload is defined by a typename template.
The payload is the data that the packet contains. It can be a part of a list in case of Multi Packets usage.